Currently, polyether and polyester based polyurethanes are utilized for a wide variety of molded articles. An illustrative but nonlimiting example of this type of molded article would include an end cap for a filter. Both the polyether material and polyester material have a tendency to degrade in oil or fuel solutions. Polyetherpolyurethane material was developed for improved chemical resistance in oil and fuel environments and is remarkably durable in these applications. However, the polyetherpolyurethane material has a very low viscosity that creates tremendous processing problems. In production, speed is of the essence. Therefore, the mold must be moved at a very rapid rate of speed. It is this movement that causes low viscosity polyetherpolyurethane to slosh within the mold so that the molded article will not have a smooth and consistent finish. This sloshing will create variance not only in the thickness of the molded article but also in the appearance of the molded article. In addition, thinly cured pieces of polyurethane (flash), can also be created due to the sloshing of the low viscosity fluid. This flash can break-off from the end cap, which can inhibit the flow of oil or fuel through the filter or through the engine.
The present invention is directed to overcoming one or more of the problems set forth above.